Improvement in convicts  shackles



J. L. QUACKENBUSH.

couvzc'rs SHACKLES.

' Patented March 20,1877.

' mvnnom ATTOBHEYS.

UNITED STATES PATENT QEFTGE.

JAY L. QUAOKENBUSH, OF PORTLAND, OREGON.

IMPROVEMENT IN CONVICTS SHACKLES.

' Specification forming part of Letters Patent No. l8,540, dated March 20, 1877; application filed January 29, 1877.

To all whom it may concern:

Be it known that I, JAY L. QUAOKENBUSH, of Portland, in the county of Multnomah and State of Oregon, have invented a new and useful Improvement in Convicts Shackles, of which the following is a specification:

Figure 1 is a longitudinal section of a shackle, taken through the line a: as, Fig. 2. Fig. 2 is an edge view of the same.

Similar letters of reference indicate corresponding parts.

The object of this invention is toimprove the construction of convicts shackles in such a way as to prevent the prisoner from removing his shackles, and at the same time enable the keeper to readily remove and replace them, as required.

The invention consists in the combination of the hidden screws with the semi-cylindrical jaws of the half-rin g parts of the shackle, having a screw-thread out upon their outer surface, and the caps having a screw-thread out upon theirinner surface,.as hereinafter fully described.

A and B represent the two parts that form the ring of the shackle. The ends of the parts A B abut squarely against each other, and upon the outer or convex sides of said ends are formed jaws a b, each of which is made of semi-cylindrical form, and upon their outer surface is cut a screw-thread to fit into the screw-thread cut in the inner surface of the cylindrical caps (J, the ends of which fit against or are sunk into the ends of the half-ring parts A B. The caps O are secured in place upon the jaws a. b by screws D, which screw through the jaw b into a recess in the inner surface of the cap 0, the head of the screw D sinking into a countersink in the said jaw 11.

In the inner part of the jaw 00 is formed a re-- cess to receive the head of the screw D, when the said screw is run out to allow the cap G to be screwed off.

In the cap 0, and in the outer part of the jaw 0., is formed a slot to allow a key, E, to be inserted to turn the screw D in and out.

The key E may be made with a fork to enter holes in the heads of the screws D, or may be otherwise formed to take hold of and turn the said screws. The size of the cavity above the screw-head and the narrowness of the key-hole or slot prevent thetaking of an impression.

Having thus described myinvention, I claim as new and desire to secure by Letters Patent The combination of the hidden screws D with the semi-cylindrical jaws a b of the halfring parts A B of the shackle, the jaws a. I) having a screw-thread cut upon their outer surface, and the caps 0 having screw-threads out upon their inner surface, substantially as herein shown and described.

JAY L. QUAOKENBUSH.

Witnesses SETH L. POPE, ARTHUR HAINE. 

